QS is generational, and newer versions will be much better in quality than older ones, and have some more throughput too.
Important note: ARC gpus all have the same qs engine right now (A780 = A310), so even an arc a310 will decimate any cpu qs and will be much faster than any nvidia hardware encoder too. (qs encoder in a310 is slightly handicapped by lower vram bandwidth and size, but it is negligible)